The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
An internal combustion engine includes an intake camshaft that controls the flow of air entering the engine. The air is combined with fuel and combusted within a cylinder. The combustion drives a piston which, in turn, drives a crankshaft to produce drive torque. Exhaust gas from the combustion exits the engine by control of an exhaust camshaft.
One or more sensors detect rotation of the camshafts and/or the crankshaft. Sensor signals indicate whether the engine is rotating and thus, operational. Diagnostics are performed to confirm operation of the sensors and the engine. In some cases, the diagnostics do not run when the engine is starting to rotate, which may prevent the engine from starting. In other cases, the diagnostics set faults when the engine stops rotating. This may result in improper detection of faults, which may impact drivability.